Rotary pump



Sept. 2l, 1965 E, E. COCK 3,207,078

ROTARY PUMP Filed Jan. l0, 1965 United States Patent O 3,207,078 ROTARYPUMP Ernest E. Cook, Anoka, Minn., assigner, by mesne assignments, toHypro, Inc., Minneapolis, Minn., a corporation of Ohio Filed Jan. 10,1963, Ser. No. 250,621 1 Claim. (Cl. 10S- 136) This invention relatesgenerally to rotary pumps, and pertains more particularly to a pumpprovided with an eccentrically mounted rotor having a plurality ofgrooves or recesses for the accommodation of a number of centrifugallyactuated impeller rollers that provide the pumping action as theytraverse a curvilinear path within a pumping chamber.

One object of the invention is to provide a rotary pump having a largevolumetric capacity for its size. More specifically, it is an aim of theinvention to provide a pump that employs an axial flow from one endthereof to the other with increased et`n`ciency derived in part from theparticular method of porting.

' Another object of the invention is to provide a rotary pump that isextremely simple and which can be manufactured at a low cost. In thisregard, it is contemplated that the pump housing will consist ofduplicate halves that can readily be molded from appropriate plasticmaterial.

A further object of the invention is to provide a rotary pump that canvery easily be driven from either end, thereby making it unnecessary toexercise any degree of care as far as the axial orientation of the pumpis concerned when coupling the pump to a drive motor.

Still another object of the invention is to provide a pump that can becompletely submerged and which is capable of pumping to the bottom of acontainer. It is also an aim of the invention to provide a pump that canbe inserted into small-mouthed containers, such as bottles and the like.

Yet another object of the invention is to provide a pump capable ofproducing a relatively constant flow which for all intents and purposeswill be virtually pulse-free.

It is also within the purview of the invention to provide a pump of theenvisaged character, the basic design of which can be modified for abalanced rotor type of operation.

These and other objects and advantages of this invention will more fullyappear from the following description, made in connection with theaccompanying drawing, wherein like reference characters refer to thesame or similar parts throughout the several views and in which:

` FIGURE l is a vertical sectional view showing the pump of the instantinvention in actual use;

FIGURE 2 is a sectional view taken in the direction of line 2`2`ofFIGURE l;

FIGURE 3 is a sectional View taken in the direction of line 3-3 ofFIGURE l;

FIGURE 4 is a sectional view taken in the direction of line 4-4 ofFIGURE l; v

FIGURE 5 is a vertical sectional view in perspective of the pumphousing, the rotor having been removed in order to show to betteradvantage the construction of the two identical housing halves; and

FIGURE 6 is a perspective view of the grooved pump rotor.

Referring now in detail to the drawing, the pump selected for thepurpose of exemplfying the invention has been designated in its entiretyby the reference numeral 10. As can be seen from FIGURES 1 and 5, thepump 10 comprises a housing which includes two identical halves orsections labeled 12a and 12b. It is planned that these housing halves12a and 12b be molded from a suitable plastic material, such as nylon.

In their assembled relation, the housing halves 12a and 12b provide apumping chamber 14 formed by the 3,207,078 Patented Sept. 2l, 1965 ICCside walls 16a, 16b and the end walls 18a, 18b. The housing halves 12aand 12b abut each other, and for the purpose of aligning the two halvesor sections with respect to each other a pair of dowel pins 20a and 201)are formed integrally with the halves 12a and 12b. These pins 20a and20b are appropriately received in properly located holes, one such holeappearing as 22a in FIGURE 4.

In order to facilitate the ensuing description, a diametrical plane 24may be considered to be present. This plane may be considered to beperpendicular to the plane of the drawing as viewed in FIGURE 1, andsuch plane has also been indicated in certain of the other views.Integral with the end walls 18a, 18b are sleeve bearings 26a, 26b. Thecommon axis (when the housing halves 12a, 12b are assembled) of thesesleeve bearings 26a, 26b, lies in the plane labeled 24. However, theaxis that has just been referred to is nearer the side walls 16a, 16b ina direction toward the viewer. In other words, as evident from FIGURES2, 3, and 4, the common axis for the sleeve bearings 26a, 26b is offsetwith respect to the center of the pumping chamber 14 in order to providea desired eccentricity that will be presently referred t0.

It will also be of help in appreciating the advantages flowing from thepresent invention to make reference to a plane 28 which is perpendicularto the previously mentioned plane 24. The plane 28 intersects the plane24 aft of the common axis for the sleeve bearings 26a, 26b. Havingalluded to the plane 28, it will now be explained that the end walls18a, 18h are formed with outer arcuate openings 30a, 30b, these arcuateopenings being innerjacent the side walls 16a, 16h. Located radiallyinwardly from the arcuate openings 30a, 30b are additional arcuateopenings 32a, 321; which cane be made slightly wider at one end than theother owing to the eccentric or offset location of the sleeve bearings26a, 26b. Thus, the arcuate openings 30a, 30h and 32a, 32b are separatedby arcuate strips 34a, 34b which strips are of course integral with therespective end walls 18a, 18b. It will be observed from FIGURES 2 and 3that the arcuate openings 30a, 30b, 32a, and 32b are generally bisectedby the plane 28. It is also to be noted that these arcuate openingssubtend an arc of approximately or what amounts to a quadrant at oneside of the diametrical plane 24 as far as the end wall-18a is concernedand the opposite side of the plane 24, as far as the end wall 18b isconcerned, this being the relationship when the two halves 12a, 12b areassembled as in FIGURE 5.

As can be seen from FIGURES 1 and 5, the housing halves 12a, 12b areformed so that skirt portions 36a, 36b project in opposite directionsfrom the end walls 18a, 18b. These skirt portions 36a, 36b are formedwith notches 38a, 38b having supporting feet 40a, 40b therebetween. Thenotches 38a or 38b, as the case may be, permit the intake of fluid tothe pump 10 under certain circumstances, as will be presently mademanifest.

At this time attention is directed to a rotor denoted by the numeral 42.As with the housing parts or halves 12a, 12b, the rotor 42 may be moldedfrom a suitable plastic material, such as nylon. The diameter of therotor 42 is equal to the radial distance measured from the plane 28along the plane 24 toward the reader, which is the shortest distancebetween the axis of the sleeve bearings 26a, 26b and the side walls 16a,16b. The rotor 42 has a length substantially equal to the length of thepumping chamber 14. Thus, when the two halves 12a, 12b are placed inabutting relation, such as appears in FIGURES l and 5, it will beappreciated that the rotor 42 occupies substantially the full height ofthe chamber 14. Actually, the lower end wall 18a serves as a thrustbearing or support upon which the rotor 42 rotates. Although the numberis susceptable to variation, it will be observed that the rotor 42 isformed with four longitudinal grooves or recesses 44, each havingparallel sides and extending the full length of the rotor. For thepurpose of making the rotor rotatable, a shaft 46 is press-fitted into abore extending longitudinally through the rotor 42, this shaft havingits ends projecting oppositely as can be seen in FIGURE 1.

Inasmuch as four grooves or recesses 44 have been selected, the samenumber of cylindrical rollers 48a, 48b, 48C, and 48d are employed. Theserollers which act as pistons or vanes, are freely disposed within therecesses 44 and have a length coextensive therewith. It will beappreciated that the recesses 44 are actually radially directed andtherefore the cylindrical roller 48a- 48d are free to move radiallywithin these recesses, being guided in such a movement by the parallelsides of the various recesses.

A close inspection of FIGURES 1 and 5 will reveal that the skirts 36a,3611 are formed with counterbores 50a, 5013, thereby providing shoulders52a, SZb. The upper counterbore Sb accommodates the lower end of avertical delivery tube 54. The upper end of the tube 54 is received in anozzle head 56 having a laterally directed discharge spout 5S.

For the purpose of operating the pump is a drive motor 60 provided witha downwardly directed shaft 62. The shaft 62 is connected through theagency of an upper coupling member 64 to an intermediate shaft 66, thenozzle head 56 being configured so as to accommodate an O-ring packingmember 68. The lower end of the intermediate shaft 66 is connected tothe pump shaft 46 by reason of a second coupling member 70.

While the pump 10 can be used for a variety of purposes, it is believedthat it will possess especial utility in pumping liquids fromsmall-mouthed containers such as bottles and the like. Therefore, inFIGURE 1 the pump 10 has been shown as having been inserted through themouth of a bottle 72 containing liquid 74 therein which is to be removedfrom such container. It will be appreciated that the nozzle head 56 canbe designed with a suitable seal for the particular type and size ofbottle 72. In this regard, if the pump 10 is to be employed for pumpingwater from a bottle, say for the purpose of making a beverage, then thehead S6 will be preferably designed with a resilient ring that can bepressed into the mouth of the bottle 72, appropriate provision beingmade for venting the bottle as its contents are withdrawn.

Having presented the foregoing information, the operation of the pump 10will now be described. It will be noted from FIGURE 4 that an arrow 76indicates the direction in which the motor 60 drives or rotates therotor 4Z. It will also be of assistance to assign reference numerals tovarious lunate regions in order to facilitate the operationaldescription. With this in mind, reference numerals 78, 80, 82 and 84have been used to designate certain regions in which various pressureconditions exist during the pumping operation. Additional regionslabeled 86, 88 and 90 appear in FIG- URE 4, these regions being at thebase of the various recesses 44 with the exceptionlof the recessappearing in the six oclock position of this particular figure.

What occurs as the roller 48a is advanced from the six oclock positionto the three oclock position of FIG- URE 4 is that the lower end of theroller 48a is moved from a position overlying a solid section of the endwall 18a to a position where it rests on the arcuate strip 24a and thusoverlies portions of the openings or inlet ports 30a, 32a. In the sixoclock position, it will be discerned that the roller 48a occupies aposition in its recess 44 which is for all intents and purposes againstthe base of this particular recess. However, as it is moved in itscounterclockwise path, it is forced outwardly by centrifugal action andtraverses what has been labeled the lunate region 78. As can readily bediscerned from FIGURE 4, this lunate region 78, which of course extendsfrom the lower end wall 18a to the upper end wall 18h, increases incubic volume as measured in a counterclockwise direction. Likewise,inasmuch as the roller 48a is moving radially outwardly, the region 86continually increases in volume. The increase in volume of the tworegions 78 and 86 causes a reduced pressure condition to exist, and asthe lower end of the roller 48a moves into juxtaposition with thearcuate openings 30a, 32a some of the liquid 74 is drawn upwardly intothese regions 78, 86.

The suction thus produced continues at an accelerated rate as the roller48a is progressed toward the twelve oclock position of FIGURE 4.However, the suction ceases when the roller 48a reaches a superimposedposition with the trailing edges of the arcuate openings 30a, 32b.However, when the roller 48a reaches the trailing edges of theseparticular arcuate openings, the following roller 48d is just beginningto move into juxtaposition with the leading or advance edges of theseparticular openings.

The continued advancement of the rollers 48d and 48a carries theentrapped liquid therebetween and when the roller 48a, which is now tobe considered as leaving its twelve oclock position, reaches the leadingor advance edges of the arcuate openings 30h, 32b, these being theopenings in the upper end wall 18b, it will be appreciated that theroller 48d under these circumstances will just be leaving the lowerarcuate openings 30a, 32b and the liquid entrapped between these twoparticular rollers will be forced upwardly to the openings 30h, 32b.This is so by reason of the decrease in cubic volume of the lunateregion 82 and also the decrease in volume of the region 8S.

After passing through the nine oclock position, it will be understoodthat the roller 48a is still being urged inwardly with respect to itsparticular recess and that the region is becoming progressively smallerand will be continually reduced until the roller 48a has passed beyondthe trailing edge of the arcuate openings 30b, 32b.

From what has been said above, it is believed evident that the arcuateopenings 30a, 32a function as inlet ports, whereas the arcuate openings3017, 32b function as discharge ports. Consequently, the various rollers48a, 48b, 48e, and 48d continually and successively draw into theregions '78, 80, and 86 liquid 74 from the container 72. On the otherhand, the rollers force liquid from the regions 82, 84 and 90 due to therotation of the rotor 42 about its offset or eccentric axis. It isimportant to note that the successive positions of the various rollers48a, 48h, 48C, and 48d with respect to the arcuate openings 30a, 30b,32a and 32b are such that produce a pumping action of maximumeffectiveness with the rollers acting as pistons or vanes as previouslymentioned. Not only does one -roller arrive at the advance or leadingedges of the inlet ports (openings 30a and 32a) just when the rollerahead is leaving these ports, the same thing happening at the dischargeports (openings 30b .and 32b), but it is to be distinctly noted that useis made of the vregions 86, 88 and 90 between the various rollers andthe base of each recess 44. Stated somewhat differently, in thedisclosed construction, a pumping action occurs via two parallel paths,so to speak. Thus, for a given size of pump, a high volume of liquid canbe pumped and is pumped in a non-pulsating fashion. It is also to bediscerned that the flow of liquid is in an axial direction withoutrequiring a reversal of liquid movement or even an abrupt change in thedirection in which the liquid moves. Hence, a highly efficient pump isproduced when following the teachings of the present invention.

It will, of course, be understood that various changes may be made inthe form, details arrangements and proportions of the parts withoutdeparting from the scope of this invention as set forth in the appendedclaim.

What is claimed is:

A rotary pump comprising:

(a) housing means forming an elongated pumping chamber therewithinhaving an imperforate sidewall and opposite end walls, one end wallhaving an inlet port at one angular location and the other end wallhaving an outlet port displaced angularly from said inlet port,

(b) a cylindrical rotor Within said pumping chamber journaled forrotation about an axis offset from the longitudinal axis of said pumpingchamber, said rotor having a plurality of radially directed recessesextending from one end thereof to the other, and

(c) an elongated piston member freely disposed in each of said recessesand having a length substantially coextensive to said recesses, wherebywhen said rotor is rotated about its said axis the ends of said rollerswill successively overlie said inlet and outlet ports,

(d) said housing means constituting two identical housing halvesabutting each other in a radial plane passing substantiallyperpendicularly through the axis of said rotor,

(e) said piston members being cylindrical rollers,

(f) the end wall of each housing half being recessed from the distal endthereof to provide oppositely projecting skirts for said housing means,

(g) each housing half being of molded construction and in which (h) eachend wall being provided with an integral sleeve bearing projecting intoits associated skirt, (i) said rotor having a shaft extending axiallytherethrough into said sleeve bearings to rotatably journal said rotor,

(j) the free edge of each skirt being formed with a series of spacednotches to permit ingress of liquid to said inlet port when the housinghalf containing said inlet port is resting on a at horizontal surface.

References Cited by the Examiner UNITED STATES PATENTS KARL I. ALBRECHT,Primary Examiner.

LAURENCE V. EFNER, JOSEPH H. BRANSON, IR.,

Examiners.

